How to detect "leave a page" exactly if user opens other page in new tab? [duplicate]

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• How to detect when a tab is focused or not in Chrome with Javascript? 6 answers

I wanna exploit a special case when user leaves a page. I create a method to do something when user leaves a page. But, if user is staying on this page, and clicks a link to open new page in new tab. So, does user leave page?

Can you tell me a hint? Thank you!

p/s: I'm using MVC 5 and I can use jQuery/javascript.